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Herein, the tribological behavior of 316L stainless steel (SS) fabricated using metal extrusion additive manufacturing (MEAM) is investigated both under dry and simulated body fluid (SBF)‐lubricated conditions. The results and mechanisms are compared with those of 316L SS fabricated via selective laser melting (SLM) and hot rolling (HR). Under dry‐friction conditions, the 316L SS fabricated via MEAM shows inferior tribological performance compared with those fabricated via SLM and HR, primarily because of its lower initial hardness and better plasticity, which increase both abrasive and adhesive wear. Under SBF‐lubricated conditions, the tribological performance of the 316L SS fabricated via MEAM is comparable to that fabricated via HR and superior to that fabricated via SLM. The wear rate of the MEAM‐fabricated 316L SS is 16.8% and 3.2% lower than SLM‐ and HR‐fabricated, respectively. The numerous pores on 316L SS serve as traps for wear particles, which contribute to the reduction of three‐body wear. In terms of wear under SBF‐lubricated conditions, MEAM technology appears to be a promising method for the fabrication of customized 316L orthopedic implants. [ABSTRACT FROM AUTHOR]

The application of superamphiphobic coatings improves the surface's ability to repel fluids, thereby greatly enhancing its various functions, including anti-fouling, anti-corrosion, anti-icing, anti-bacterial, and self-cleaning properties. This maximizes the material's potential for industrial applications. This work utilized the agglomeration phenomenon exhibited by nano-spherical titanium dioxide (TiO2) particles to fabricate 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES) modified TiO2 (TiO2@fluoroPOS) fillers with low surface energy. This was achieved through the in-situ formation of protective armor on the surface of the agglomerates using the sol-gel method and fluorination modification. Polyvinylidene fluoride-tetrafluoropropylene (PVDF-HFP) and TiO2@fluoroPOS fillers were combined using a spraying technique to prepare P/TiO2@fluoroPOS coatings with superamphiphobicity. Relying on the abundance of papillae, micropores, and other tiny spaces on the surface, the coating can capture a stable air film and reject a variety of liquids. When the coatings were immersed in solutions of 2 mol/L HCl, NaCl, and NaOH for a duration of 12 h, they retained their exceptional superamphiphobic properties. Owing to the combined influence of the armor structure and the organic binder, the coating exhibited good liquid repellency during water jetting and sandpaper abrasion tests. Furthermore, the coating has shown exceptional efficacy in terms of its ability to be anti-icing, anti-waxing, and self-cleaning. [ABSTRACT FROM AUTHOR]

Coal dust particles adhering to a camera lens reduce its light transmittance, which deteriorates the performance of the camera and may lead to serious problems with mining equipment that requires visual ability. Aiming at improving coal dust removal and cleaning technologies, the adhesion behavior of coal dust with fused silica is studied here. Experiments were conducted from microscopic and statistical points of view. The adhesion force between a single coal dust particle and fused silica is tested using atomic force microscopy (AFM), and the number and size distribution of large amounts of coal dust particles on fused silica are tested using a home-made adhesion experimental platform and image processing method. The results show that the adhesion force increases at high relative humidity (RH); it is dominated by van der Waals forces at low RH and capillary forces at high RH. The fused silica glass surface is predominantly covered by small-sized coal dust particles, and the total number of particles as well as the proportion of large-sized particles increases with RH. The theoretical values of van der Waals and capillary forces are significantly larger than the experimental values, owing to the irregular shape and roughness of the surface of the coal dust. [ABSTRACT FROM AUTHOR]

Lilium brownii var. viridulum (BB) and L. davidii var. unicolor (AdAd) are grown for edible in China, but their breeding lags far more than other ornamental lily breeding. To improve the situation, F1 BA hybrids were used as seed parents to cross with AdAd and other diploid Asiatic lilies (AA). The results showed that the F1 BA hybrids could produce BC1 progenies. The average seedlings obtained from the combinations per fruit were very variable from 1.7 to 22.5, indicating that their compatibilities were different depending on their males. Among the 18 progenies with genomic in situ hybridization (GISH), ten of them were diploid (2n = 2x = 24), two are aneuploid-near diploid (2n = 2x ± 1), and other six were allotriploid (2n = 3x = 36); and all of them contain much more recombinant chromosomes and breakpoints than other distant lily hybrids. We concluded that F1 LA hybrids produced much more n functional egg cells than 2n functional egg cells and this would pay a new way to realize lily ingression breeding at diploid ploidy level. [ABSTRACT FROM AUTHOR]

In order to improve the performance of 17-4PH under wear conditions (e.g., gears, etc.) and reduce the cost of metal additive manufacturing, TiC needs to be added to 17-4PH to improve its wear resistance. Micron-sized TiC-reinforced 17-4PH stainless steel composites with different contents (0–15 wt%) have been prepared by fused filament fabrication 3D printing for the first time. The effects of TiC content on the structure and properties of composites were studied by XRD, SEM, and sliding wear. The obtained results show that the microstructure of TiC-reinforced 17-4PH stainless steel composites mainly consists of austenite. With the increase in TiC content, the grain size is obviously refined, and the average grain size decreases from 65.58 μm to 19.41 μm. The relative densities of the composites are maintained above 95% with the addition of TiC. The interfaces between TiC particles and the 17-4PH matrix are metallurgical bonds. The hardness of the composites increases and then decreases with increasing TiC content, and the maximum hardness (434 HV) is obtained after adding 10 wt.% of TiC content. The wear rate of the composites was reduced from 2.191 × 10−5 mm3 /(N‧m) to 0.509 × 10−5 mm3 /(N‧m), which is a 3.3-fold increase in wear resistance. The COF value declines with the addition of TiC. The reasons for the significant improvement in the composites' performance are fine grain strengthening, solid solution strengthening, and second phase strengthening. The wear mechanisms are mainly abrasive and adhesive wear. Compared to the 10 wt% TiC composites, the 15 wt% TiC composites show limited improvement in wear resistance due to more microcracks and TiC agglomeration. [ABSTRACT FROM AUTHOR]

Asiatic lily cultivars, bred by hybridization and (or) chromosome doubling of species of section Sinomartagon of Lilium, are diploid, triploid, or tetraploid, but the homology of the genomes among species of section Sinomartagon and Asiatic lilies remains unclear. In the present research, two tetraploid Asiatic cultivars were analyzed, using 45S rDNA as probe, for their FISH karyotypes and their chromosomal association, anaphase I, telophase II, and pollen viability were surveyed to assess the multivalent segregation. Chromosomal assortment of six progenies of the two tetraploid cultivars were also investigated. The results showed that the tetraploid cultivars had similar FISH karyotypes, they predominantly formed multivalents, and these were equally separated because their anaphase I, telophase II, and pollen viability were similar to those of diploid species. Apart from minor variations, FISH karyotypes of progenies were similar to each other and to their parents. Based on these results and considering the high crossability among species of section Sinomartagon and (or) Asiatic lilies, we concluded that species of section Sinomartagon and their resulting cultivars share a common genome; thus, polyploidy Asiatic lilies are autopolyploid. Keywords: autotetraploid, biological species, 45S rDNA, homologous, multivalent. Les cultivars de lys asiatique, developpes par hybridation ou doublement chromosomique a partir des especes de la section Sinomartagon du genre Lilium, sont diplo'ides, triploides ou tetraplo'ides, mais l'homologie entre les genomes au sein des especes de la section Sinomartagon et les lys asiatiques demeure nebuleuse. Dans ce travail, deux cultivars tetraplo'ides asiatiques ont ete analyses, au moyen d'une sonde d'ADNr 45S, en ce qui a trait a leur caryotype FISH, aux associations chromosomiques en anaphase I et en telophase II, ainsi qu'en matiere de viabilite du pollen pour examiner la segregation des multivalents. L'assortiment chromosomique au sein de six progenitures des deux cultivars a egalement ete examine. Les resultats ont montre que les cultivars tetraploides presentaient des caiyotypes FISH similaires, qu'ils formaient des multivalents de maniere predominante et que ceux-ci se separaient de maniere egale puisque leur division en anaphase I et en telophase II ainsi que la viabilite de leur pollen etaient toutes normales tout comme chez les especes diplo'ides. En dehors de differences mineures, les caryotypes FISH des progenitures etaient semblables entre eux et similaires a ceux des parents. Sur la base de ces resultats et de la forte aptitude au croisement entre les especes de la section Sinomartagon et les lys asiatiques, les auteurs concluent que les especes de la section Sinomartagon et les cultivars qui en sont tires partagent un genome commun; ainsi, les lys asiatiques s'averent des autopolyploides. [Traduit par la Redaction] Mots-cles : autotetraploide, espece biologique, ADNr 45S, homologue, multivalent., Introduction Asiatic lily, the largest group of modern lily cultivars, is bred by hybridization and (or) chromosome doubling from species of section Sinomartagon in Lilium L. of Liliaceae (McRae 1998; [...]

To increase the residual stress stability of Au films while reducing the residual stress level, the effect of deposition temperature on long-term residual stress evolution of Au films under different conditions were studied. Au films with a thickness of 360 nm were deposited using e-beam evaporation on fused silica under different temperatures. Observations and comparisons were made of the microstructures of Au films deposited under different temperatures. Results showed that by increasing the deposition temperature, a more compact microstructure of Au film was obtained, which was manifested in increased grain size and reduced grain-boundary voids. After deposition, a combined process consisting of natural placement and 80 °C thermal holding was conducted on the Au films, and the residual stresses were monitored using the curvature-based technique. Results showed that the initial tensile residual stress of the as-deposited film decreased with the deposition temperature. The Au films with higher deposition temperatures showed better residual stress stability, maintaining low stress levels in the subsequent long-term combination of natural placement and thermal holding. The mechanism was discussed based on the differences in microstructure. Comparisons were made between post-deposition annealing and increased deposition temperature. [ABSTRACT FROM AUTHOR]

Background: Most human papillomavirus (HPV)‐positive women recover from infections and do not develop cervical intraepithelial neoplasia (CIN) and cervical cancer. Additional triage approaches are needed to reduce unnecessary colposcopy referrals. The aim of this study is to determine the high‐risk HPV prevalence in a hospital‐based population and to evaluate the performance of p16/Ki‐67 dual‐stain test for the triage of high‐risk HPV‐positive women to detect precursor lesions and cervical cancer compared with the ThinPrep cytologic test (TCT). Methods: In a hospital‐based population, 100,801 women were provided with a primary HPV DNA test and only women with high‐risk HPV infections were triaged using TCT and p16/Ki‐67 dual‐stain test. CIN2 or worse (≥CIN2) or CIN3 or worse (≥CIN3) were defined as the clinical end points. Results: The p16/Ki‐67 dual‐stain indicated a statistically significant higher sensitivity (82.8% vs. 66.7%%), specificity (51.6% vs. 44.4%), positive predictive value (33.2% vs. 25.8%), negative predictive value (91.2% vs. 82.1%), and accuracy (58.6% vs. 49.4%) compared with TCT examination within ≥CIN2 cases. Similar patterns were observed for the ≥CIN3 end point. Conclusions: Our study demonstrated that p16/Ki‐67 dual‐stain test could achieve better performance compared with TCT examination for ≥CIN2 or ≥ CIN3 detection, representing a promising approach as a specific and efficient triage strategy for high‐risk HPV‐positive women. Our study demonstrated that p16/Ki‐67 dual‐stain could achieve better performance compared with ThinPrep cytologic test for ≥CIN2 or ≥ CIN3 detection. It represents a promising approach as the "second‐line" triage test for human papillomavirus‐positive women, especially in China, where the experienced cytotechnologist and standardized professional training are scarce. [ABSTRACT FROM AUTHOR]